1. Field of the Invention
The present invention relates to a proper coupling confirming mechanism for an electric connector for connecting contactors of an electric circuit on a vehicle.
2. Description of the Prior Art
The electric connector has a pair of connector housings, which are mated together to join electrically the male and female contactors contained therein, and is provided with locking means including flexible locking arm and a locking arm catching member between the pair of connector housings to lock the pair of connector housings to each other. In manually coupling the pair of connector housings, the coupling and locking of the pair of connector housings are confirmed through the tactile recognition of coupling, the auditory recognition of locking sound and the visual inspection of the appearance of the electric connector. However, since a large number of electric connectors need to be coupled on the vehicle and the working environment is not necessarily favorable for the sensational confirmation of the coupling of the electric connectors, it is possible that some electric connectors are not properly coupled.
To reduce this problem, an electrically efficient coupling confirming mechanism as shown in FIGS. 6 and 7 is proposed in Japanese Utility Model Laid-open (Kokai) No. 61-186180. This coupling confirming mechanism comprises a pair of electrical contactors b.sub.1 and b.sub.2 contained in a first connector housing a in an electrically separate condition, and an elastic tongue e contained in a second connector housing d to force the pair of electrical contactors b.sub.1 and b.sub.2 into contact with each other. The first connector housing a is provided with a protrusion c which prevents connectors b.sub.1 and b.sub.2 from forcible contact when the first connector housing a and the second connector housing d are improperly coupled.
This coupling confirming mechanism, however, has the following drawbacks. As shown in FIG. 6, since the pair of electrical contactors b.sub.1 and b.sub.2 disposed close to each other in the first connector housing a and any insulating means is not provided between the pair of electrical contactors b.sub.1 and b.sub.2, it is possible that the electrical contactors b.sub.1 and b.sub.2 remain in contact with each other before the coupling of the first connector housing a and the second connector housing d when either the electrical contactor b.sub.1 or b.sub.2 or both the electrical contactors b.sub.1 and b.sub.2 are deformed or are disposed incorrectly within the first connector housing a. Furthermore, since the elastic tongue e is comparatively small and is formed of a synthetic resin integrally with the second connector housing d, the elasticity of the elastic tongue e is dependent on temperature and, under some conditions the elastic tongue e is unable to function properly, and the elastic tongue e makes the internal construction of the second connector housing d complex.